Comparative Quarterly Financial Information (Unaudited)
12 Months Ended
Oct. 31, 2011
Quarterly Financial Information Disclosure [Abstract]  
Comparative Quarterly Financial Information (Unaudited)

23. Comparative Quarterly Financial Information (Unaudited)

       2011    
(in thousands, except per share data)First QuarterSecond QuarterThird QuarterFourth Quarter Full Year
            
 Total revenues$ 312,287$ 325,838$ 327,303$ 294,603$ 1,260,031
 Operating income$ 103,018$ 117,037$ 115,674$ 101,928$ 437,657
 Net income attributable to Eaton Vance Corp. shareholders$ 37,535$ 62,479$ 68,068$ 46,820$ 214,902
 Earnings per Share:          
  Basic$ 0.31$ 0.53$ 0.58$ 0.41$ 1.82
  Diluted$ 0.30$ 0.50$ 0.55$ 0.40$ 1.75
            
       2010    
(in thousands, except per share data)First QuarterSecond QuarterThird QuarterFourth Quarter Full Year
            
 Total revenues$ 272,035$ 272,953$ 273,079$ 303,594$ 1,121,661
 Operating income$ 87,347$ 81,089$ 78,762$ 106,084$ 353,282
 Net income attributable to Eaton Vance Corp. shareholders$ 46,242$ 36,000$ 41,750$ 50,306$ 174,298
 Earnings per Share:          
  Basic$ 0.39$ 0.30$ 0.35$ 0.43$ 1.47
  Diluted$ 0.37$ 0.29$ 0.34$ 0.41$ 1.40